the instructions you've referenced are for a physical appliance with a serial console port. BIG-IP VE has no serial port, so they don't apply (or a lights out manager)
My guess is that you might be accessing the VMplayer console over a remote desktop or terminal services session. This can have an adverse affect on the login. You'll observe that key repeat occurs. Usually it comes into play after you've typed "root" and "enter", wherein your password will actually come out as "defffffffffault" or some such variant. If you see that you're typing into the console and hit a keyboard repeat issue in general, you know you have the problem.
You can login to the Big-IP VE console through VMplayer by locally attaching to the workstation with a keyboard/monitor/mouse. (or, you can disable keyboard repeat in the Virtual Machine BIOS for the VE)
Once you're past that and have the mgmt port configured, you can access the BIG-IP over ssh and https so you won't need to bother with
the VGA console anymore.